1. Field of the Invention
The present invention relates to antibiotics 4"-deoxy-6-O-methyl-erythromycins and the salts thereof which are useful as antibacterial agents.
2. DESCRIPTION OF THE PRIOR ART
Many erythromycin derivatives have been prepared to improve their biological and pharmacological properties. For example, it is reported that 6-O-methyl and 6,11-di-O-methyl derivatives of erythromycins are more stable under acidic conditions and have stronger antibacterial activity especially, in vivo antibacterial activity than erythromycins when administered orally (U.S. Pat. No. 4,331,803 and European Pat. No. 80,818). Furthermore, 4"-deoxyerythromycin A and B are reported in Japanese Patent Application Laid-Open No. 49396/83.